The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Red_Hen on June 25, 2012, 09:29:31 PM

Title: Checked FD - uh oh . . .
Post by: Red_Hen on June 25, 2012, 09:29:31 PM
Hi Gang,

My R65 may be taking a trip to Sedalia, MO - I checked the FD fluid and I couldn't see any indication of fluid.  I added about a bottle of Castrol 80/90 and now she's full to the brim.

I'll have to watch it - it is possible the "O' rings I just read in a recent post are kaput.  Hopefully I didn't do any damage to the FD unit by riding around with low oil.  Most of my trips on Tina are around town.  She seems to be running okay.

Title: Re: Checked FD - uh oh . . .
Post by: Bob_Roller on June 25, 2012, 10:28:14 PM
Do you have any indications of leakage from the final drive ?

How full is it, full to the small over flow port at the back of the final drive ?
Title: Re: Checked FD - uh oh . . .
Post by: nhmaf on June 25, 2012, 11:00:54 PM
+1 with Bob - it should only be filled up to the bottom threads in the fill/check port at the 9o'clock position (back edge) for the final drive.   If you overfill it, you will likely encourage seals to start leaking when the things heats up while driving on the highway.

It is rare, but not unknown, for the seal at the FRONT of the final drive to manage to leak fluid FORWARD into the drive shaft - this is usually most apparent when taking off the clamp of the rubber boot by the back of the transmission and seeing a cup of oil come out - normally there should only be ~120cc of oil in the drive shaft area... but, if you aren't seeing leaks out the final drive or inside the brake hub, that stuff has got to be going somewhere.
Title: Re: Checked FD - uh oh . . .
Post by: Barry on June 26, 2012, 06:38:34 AM
Quote
Hopefully I didn't do any damage to the FD unit by riding around with low oil.Most of my trips on Tina are around town.

As long as there was enough oil in there to wet the crown wheel it may not have come to any harm from low speed use. Best thing is to drain it and see if there is any debris on the drain plug.


Quote
I added about a bottle of Castrol 80/90 and now she's full to the brim.

What size bottle would that be? The total fill for your final drive is only 350cc. Oil can and does move about between the 3 transmission items but I wouldn't have thought as much as that. I've experienced it going from the drive shaft to the final drive but not the other way around.
Title: Re: Checked FD - uh oh . . .
Post by: Red_Hen on June 26, 2012, 06:42:37 AM
Thanks guys - I did not realize the fill hole is the 9 o'clock position - thought it had to go all the way to the top plug - I'll drain, measure 350cc's and refill.  I guess it may have been okay - I have a Clymers book which covers several model Airheads - I thought I read the gear oil was supposed to be filled to the top.

Barry - the bottles is one US Quart.  And no, Bob, there has not been any leakage.
Title: Re: Checked FD - uh oh . . .
Post by: Red_Hen on June 26, 2012, 08:47:58 AM
I drained the FD reservoir - there was more than 350cc's - the fluid was quite black - this is the bike that sat outside for a couple years - at any rate, the drain plug didn't have any metal shavings but did have some goo, which I cleaned.

I measured 348cc's and added 2cc's of Guard Dog, a Moly additive to the 80/90 Castrol Gear Oil - mixed it up and poured it in the reservoir.

Glad I'm a part of this group! Thanks Guys!
Title: Re: Checked FD - uh oh . . .
Post by: Julio A. on June 26, 2012, 10:19:19 AM
350cc? I thought is was 250cc's. Or was that only for the older type cardans?
Title: Re: Checked FD - uh oh . . .
Post by: Red_Hen on June 26, 2012, 10:44:00 AM
Hi Julio,

My Clymer book calls for 350cc's for an '82 year.
Title: Re: Checked FD - uh oh . . .
Post by: Barry on June 26, 2012, 02:52:03 PM
It's the 78-80 non ribbed type of final drive that takes 250cc and the level/filler plug arrangement is different too.

Ken, about the oil coming out black.  That suggests it might not have been changed in a long while. Only wear particles should discolour the oil, excepting water contamination which will turn it milky brown. So one indicator that all is well, is that the oil drained from any of the 3 transmission components should  come out pretty much the same colour it went in. Perhaps a tint darker but not black unless that's the colour when it went in.
Title: Re: Checked FD - uh oh . . .
Post by: tvrla on June 26, 2012, 07:45:13 PM
It could have had some sort of Moly additive - my first thought. If there's no shiny bits or slivers on the magnet, then it must have been doing its job.
Title: Re: Checked FD - uh oh . . .
Post by: Red_Hen on June 26, 2012, 09:17:58 PM
Barry - I believe it was dirty from whatever residue was left in the reservoir from when I first got the bike - she sat outdoors for several punishing MN winters.  

I'll change all fluids at end of season.

FWIW, tranny gear oil is golden and that was disassembled and overhauled.

Checked  drive shaft oil but did not drain it.

Title: Re: Checked FD - uh oh . . .
Post by: steven m on June 26, 2012, 09:35:24 PM
If the FD was full of goo and the bike sat for a while you might consider changing the oil in the driveshaft, getting the bike nice and hot, and then draining and putting in fresh measured amounts into both.  Then at the end of the season it will be easy to tell if your driveshaft to FD gasket is shot by the amount of oil in each.  Do not overfill the driveshaft.

Just my two cents.

Steve
Title: Re: Checked FD - uh oh . . .
Post by: Red_Hen on June 27, 2012, 06:24:38 AM
sounds like a great suggestion - thanks, Steve.

Btw, I grew up in Beverlywood, adjacent to Culver City.
Title: Re: Checked FD - uh oh . . .
Post by: steven m on June 27, 2012, 09:53:31 AM
Beverlywood is my shortcut north.  Nice neighborhood.  Not fast but free of commercial traffic.

Filling the driveshaft with oil is tedious and if you use a funnel it will result in oil all over the floor.  At least that's been my experience.  I use a small old fashioned pump oil can, filled with a measured amount and squirt it in slowly.  A pipe cleaner is handy to wrap around the shaft and measure the oil level.
Title: Changing Driveshaft Oil
Post by: Red_Hen on June 27, 2012, 03:33:38 PM
I was thinking of turning the bike upside down and filling it thru the drain plug - hole is bigger >>>  ;D

Actually, I have a syringe and fuel line for my U-Control model airplanes that I barely every fly anymore - I can measure the right amount of tranny fluid, put it in the syringe and inject it into the drive shaft hole.
Title: Re: Checked FD - uh oh . . .
Post by: Barry on June 27, 2012, 05:21:32 PM
Quote
I was thinking of turning the bike upside down and filling it thru the drain plug - hole is bigger >>>Grin


We may all laugh at the prospect but it's always worth remembering to make sure that you can remove the fill plug before draining the oil otherwise it can be tricky to get it back in again.
Title: Re: Checked FD - uh oh . . .
Post by: Bob_Roller on June 27, 2012, 05:34:34 PM
I had this happen when I got my '82 LS, first thing I did, was to drain all of the fluids and replace them .

Went to fill the driveshaft, fill plug threads in the final drive housing were stripped !!! >:( >:( >:( >:(

Got to take the final drive off disassemble it and have a machine shop install a threaded insert .
Title: Re: Checked FD - uh oh . . .
Post by: donbmw on June 27, 2012, 06:02:42 PM
Get a outboard lower unit pump. The small end that screws in the lower unit will sit in the filler holes of the transmission, drive shaft housing and rear end housing. The you just pump a measured amount that is need in each place. On my 82 R65 I have not pulled the check bolt in years on the rear end. I remove the vent on top and add the meausred amount of gear oil need. When I was removing the check bolt just about the time you and the last little amount it would start to trickle out.
Title: Re: Checked FD - uh oh . . .
Post by: bruce_launceston on June 28, 2012, 02:06:04 AM
I have a 500ml container that I bought from a laboratory supplies shop. It is tall and about 50mm diameter and has a good pouring lip along with accurate graduations and a stable base.
They had glass but I opted for a polycarbonate one. It is ideal for filling all the oil reservoirs on the R65.